Display device with integrated touch screen

ABSTRACT

Disclosed is a display device with an integrated touch screen, including a touch screen comprising a plurality of driving electrodes and sensing electrodes built in a panel; a display driver integrated circuit (IC) (i) converting a first driving pulse into a second driving pulse with a gate high voltage Vgh, wherein the second driving pulse is applied to the driving electrodes when the panel operates in a touch driving mode, (ii) receiving a plurality of sensing signals from the sensing electrodes when the panel operates in a touch driving mode, and (iii) applying a common voltage to the driving electrodes and the sensing electrodes when the panel operates in a display driving mode; and a touch IC generating the first driving pulse, wherein the first driving pulse is applied to the display driver IC, and receiving the sensing signals from the display driver IC to detect a touch.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of the Korean Patent Application No.10-2012-0026053 filed on Mar. 14, 2012, which is hereby incorporated byreference in its entirety.

BACKGROUND

The present disclosure relates to a display device, and moreparticularly, to a display device with an integrated touch screen builtin a panel.

Touch screens are a type of input device that is included in displaydevices such as Liquid Crystal Displays (LCDs), Field Emission Displays(FEDs), Plasma Display Panel (PDPs), Electroluminescent Displays (ELDs),and Electrophoretic Display (EPDs), and enables a user to inputinformation by directly touching a screen with a finger, a pen or thelike while looking at the screen of the display device.

Particularly, the demand of display devices with integrated in-cell typetouch screen, which include a plurality of built-in elements configuringthe touch screen for slimming portable terminals, such as smart phonesand tablet Personal Computers (PCs), is recently increasing.

Display devices with an integrated touch screen are categorized into anoptical type, a resistive type, a capacitive type, etc. according to asensing type. Recently, the capacitive type is mainly used forincreasing the sharpness of a screen and the accuracy of touch.

The technology of a display device with integrated capacitive-type touchscreen has been disclosed in U.S. Pat. No. 7,859,521, etc. Particularly,U.S. Pat. No. 7,859,521 discloses the technology of a display devicewith integrated mutual capacitance type touch screen.

In a related art display device with an integrated touch screendisclosed in U.S. Pat. No. 7,859,521, a plurality of common electrodesfor display are segmented into a plurality of touch driving areas andtouch sensing areas, thereby allowing a mutual capacitance to begenerated between the touch driving area and the touch sensing area.Therefore, the related art display device measures the change of amutual capacitance that occurs in touch, and thus determines whetherthere is a touch.

In order for the related art display device with an integrated touchscreen to simultaneously perform a display function and a touchfunction, a plurality of common electrodes are respectively connected toa display driver Integrated Circuit (IC) and a touch IC. Also, the touchIC needs to perform a switching function that applies a common voltageto the common electrodes when the panel is driven in a display mode andapplies signals necessary for touch to the common electrodes when thepanel is driven in a touch mode. Moreover, the intensity of a touchsensing signal needs to increase for enhancing touch sensitivity, forwhich the touch IC needs to apply a high voltage to a driving electrode.

Therefore, the related art display device with an integrated touchscreen needs to separately include a Flexible Printed Circuit (FPC) fora touch IC and an FPC for a Display Driver IC (DDI) to connect thecommon electrodes and the display driver IC. Further, a touch IC forswitching the common voltage is required to be separately manufactured.

Moreover, a separate circuit block needs to be added for applying a highvoltage to a driving electrode, and when the touch IC includes theseparate circuit block internally, the size of the touch IC is enlarged.

SUMMARY

Accordingly, the present disclosure is directed to provide a displaydevice with an integrated touch screen that substantially obviates oneor more problems due to limitations and disadvantages of the relatedart.

One aspect of the present disclosure is directed to provide a displaydevice with an integrated touch screen, in which a display driver ICinternally has a function of switching a common voltage, and by using agate high voltage that is generated in the display driver IC, a touch ICis not required to be separately manufactured.

Additional advantages and features of some embodiments of the presentinvention will be set forth in part in the description which follows andin part will become apparent to those having ordinary skill in the artupon examination of the following or may be learned from practice of thedisclosure herein. The objectives and other advantages of the inventionmay be realized and attained by the structure particularly pointed outin the written description and claims hereof as well as the appendeddrawings.

In one aspect, to achieve these and other advantages and in accordancewith the purpose of some embodiments of the invention, as embodied andbroadly described herein, a display device with an integrated touchscreen according to the present disclosure may include: a touch screencomprising a plurality of driving electrodes and sensing electrodesbuilt in a panel; a display driver integrated circuit (IC) (i)converting a first driving pulse into a second driving pulse with a gatehigh voltage Vgh, wherein the second driving pulse is applied to thedriving electrodes when the panel operates in a touch driving mode, (ii)receiving a plurality of sensing signals from the sensing electrodeswhen the panel operates in a touch driving mode, and (iii) applying acommon voltage to the driving electrodes and the sensing electrodes whenthe panel operates in a display driving mode; and a touch IC generatingthe first driving pulse, wherein the first driving pulse is applied tothe display driver IC, and receiving the sensing signals from thedisplay driver IC to detect a touch.

It is to be understood that both the foregoing general description andthe following detailed description of the present invention areexemplary and explanatory and are intended to provide furtherexplanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings included to provide a further understanding ofthe present disclosure are incorporated in and constitute a part of thisapplication. The drawings illustrate some embodiments of the inventionand together with the description serve to explain the principle of theinvention. In the drawings:

FIG. 1 is a view schematically illustrating a configuration of a displaydevice with an integrated touch screen according to some embodiments ofthe present disclosure;

FIG. 2 is a view schematically illustrating a configuration of a displaydriver IC of the display device according to additional embodiments ofthe present disclosure;

FIG. 3 is a view schematically illustrating shapes of a drivingelectrode and sensing electrode of a display device with an integratedtouch screen according to further embodiments of the present disclosure;and

FIG. 4 is a timing chart showing outputs of a touch IC and a displaydriver IC according to a driving mode of a panel, in a display devicewith an integrated touch screen according to yet further embodiments ofthe present disclosure.

DETAILED DESCRIPTION

Reference will now be made in detail to the exemplary embodiments of thepresent disclosure, examples of which are illustrated in theaccompanying drawings. Wherever possible, the same reference numberswill be used throughout the drawings to refer to the same or like parts.Detailed description of known arts will be omitted if it is determinedthat the arts can mislead the present invention.

Hereinafter, embodiments of the present disclosure will be described indetail with reference to the accompanying drawings.

In the below description, for convenience of a description, a displaydevice with an integrated touch screen according to embodiments of thepresent disclosure will be exemplified as being an LCD, but the presentinvention is not limited thereto. The present invention may be appliedto various display devices, such as FEDs, PDPs, ELDs, EPDs, etc.

FIG. 1 is a view schematically illustrating a configuration of a displaydevice with an integrated touch screen according to some embodiments ofthe present disclosure. FIG. 2 is a view schematically illustrating aconfiguration of a display driver IC according to additional embodimentsof the present disclosure.

As illustrated in FIGS. 1 and 2, the display device with an integratedtouch screen may include a touch screen 110, a display driver IC 120,and a touch IC 130.

First, the touch screen 110 may be built in an active area of a panel100 that displays a screen, and may include a plurality of drivingelectrodes 112 and a plurality of sensing electrodes 114.

Here, the driving electrodes 112 and the sensing electrodes 114 mayperform a function of a common electrode when the display device with anintegrated touch screen is driven in a display mode. Further, thedriving electrodes 112 and the sensing electrodes 114 may perform afunction of a touch driving electrode and a function of a touch sensingelectrode when the display device with an integrated touch screen isdriven in a touch mode.

In other words, the driving electrodes and sensing electrodes of thedisplay device with an integrated touch screen according to someembodiments of the present invention may perform a touch function aswell as a display function.

Hereinafter, a shape of each of the driving electrodes 112 and sensingelectrodes 114 will be described in detail with reference to FIG. 3.

FIG. 3 is a view schematically illustrating details of drivingelectrodes and sensing electrodes of a display device with an integratedtouch screen according to some embodiments of the present disclosure.

The plurality of driving electrodes 112 may be parallelly formed in awidth direction that is a gate-line (not shown) direction of the panel100 shown in FIG. 1. The plurality of sensing electrodes 114 may bedisposed between a plurality of sub driving electrodes 1120 and may beparallelly formed in a height direction that is a data-line (not shown)direction of the panel 100.

For example, as illustrated in FIG. 3, the driving electrodes 112 may bea first driving electrode TX#1 to an mth driving electrode TX#m. Each ofthe driving electrodes 112 may include n+1 number of sub drivingelectrodes 1120. Also, the sensing electrodes 114 may be a first sensingelectrode RX#1 to an nth sensing electrode RX#n. Also, in order for aplurality of sub driving electrodes 1120 to configure one drivingelectrode as illustrated in FIGS. 1 and 3, a plurality of drivingelectrode lines 1122 may be electrically connected outside the displaydrive IC 120, and then connected to the display driver IC 120. Also, thesensing electrodes 114 may be connected to the display driver IC 120through the sensing electrode lines 1142.

Each of the driving electrodes 112 may be formed as a common electrodehaving a plurality of block types that is formed to be overlapped with aplurality of unit pixel areas. Each of the sensing electrodes 114 may beformed as a common electrode having one block type that is formed to beoverlapped with the unit pixel areas.

In other words, in the embodiments above, the sub driving electrodes1120 and the sensing electrodes 114 may be formed as one commonelectrode for a plurality of unit pixel groups. The sub drivingelectrodes 1120 may be electrically connected to each other.

The plurality of driving electrodes and sensing electrodes may act as acommon electrode for driving liquid crystal and thus may be formed of atransparent material, such as an indium tin oxide (ITO) electrode.

In FIG. 3, the plurality of sub driving electrodes 1120 are illustratedas being electrically connected in an area outside the touch screen 110,but the embodiments of the present disclosure are not limited thereto.As another example, the sub driving electrodes 1120 may be electricallyconnected inside the touch screen 110.

Moreover, in the embodiments above, the common electrode may be formedin units of unit pixel groups, but the embodiments of the presentdisclosure are not limited thereto. As another example, a commonelectrode may be formed for each unit pixel, in which the commonelectrodes that are formed in the respective pixels may be electricallyconnected by a connection line and thus the sub driving electrodes andthe sensing electrodes may be formed.

Referring again to FIGS. 1 and 2, when the panel 100 operates in a touchdriving mode, the display driver IC 120 may convert a first drivingpulse into a second driving pulse with a gate high voltage Vgh and mayapply the second driving pulse to the driving electrode 112, generatinga mutual capacitance between the driving electrode 112 and the sensingelectrode 114. Also, the display driver IC 120 may receive a sensingsignal corresponding to the change amount of a mutual capacitance thatis generated from the sensing electrode 114 with a touch sensingreference voltage Vref (e.g. being a Direct Current (DC) voltage)applied thereto in touching.

Herein, the reason that applies the touch sensing reference voltage Vrefto the sensing electrode 114 is for sensing the change amount of amutual capacitance between the driving electrode 112 and the sensingelectrode 114 by the touch IC 130 using the touch sensing referencevoltage Vref (e.g. being a constant DC voltage).

When the panel 100 operates in a display driving mode, the displaydriver IC 120 may apply a common voltage Vcom to the driving electrode112 and the sensing electrode 114 such that the driving electrode 112and the sensing electrode 114 perform a function of the common electrodefor driving the liquid crystal.

For this end, as shown in FIG. 2, the display driver IC 120 may includea voltage generator 121, a driving pulse converter 123, a sync signalgenerator 125, a first switching part 127, and a second switching part129. Also, the display driver IC 120 may further include: a gate driver(not shown) that sequentially applies a scan pulse to a plurality ofgate lines (not shown); a data driver (not shown) that respectivelyapplies a plurality of image data signals to a plurality of data lines(not shown); and a controller (not shown) that controls the elements.Such elements are general elements included in the display driver IC120.

The voltage generator 121 may include: a common voltage generator 1211that generates the common voltage Vcom; a gate high voltage generator1213 that generates the gate high voltage Vgh; and a touch sensingreference voltage generator 1215 that generates the touch sensingreference voltage Vref.

In other words, the plurality of driving electrodes 112 and sensingelectrodes 114 according to some embodiments of the present disclosuremay perform a function of the common electrode and a function of thetouch electrode together. In particular, (i) the common voltagegenerator 1211 may generate the common voltage Vcom (e.g. for drivingthe liquid crystal), (ii) the gate high voltage generator 1213 maygenerate the gate high voltage Vgh corresponding to the maximum value ofthe second driving pulse applied to the driving electrodes 112, and(iii) the touch sensing reference voltage generator 1215 may generatethe touch sensing reference voltage Vref corresponding to the minimumvalue of the second driving pulse. Then, the display driver IC outputsthe common voltage Vcom in the display driving mode, and the displaydriver IC selectively outputs the gate high voltage Vgh and the touchsensing reference voltage Vref in the touch driving mode.

In one aspect, the driving pulse converter 123 converts the firstdriving pulse, generated by the touch IC 130, into the second drivingpulse.

For example, in the touch driving mode of the panel 100, when the firstdriving pulse generated by the touch IC 130 is inputted to the drivingpulse converter 123, the driving pulse converter 123 may selectivelyoutput the gate high voltage Vgh and the touch sensing reference voltageVref that are generated by the voltage generator 121, according to thefirst driving pulse.

As a result, the driving pulse converter 123 may convert the firstdriving pulse into the second driving pulse with the gate high voltageVgh as the maximum value and with the touch sensing reference voltageVref as the minimum value.

In another aspect, the sync signal generator 125 generates a first syncsignal indicating the touch driving mode and a second sync signalindicating the display driving mode.

For example, the sync signal generator 125 may generate the first syncsignal indicating the touch driving mode at an image output time whenthe panel 100 operates in the touch driving mode. Moreover, and the syncsignal generator 125 may generate the second sync signal indicating thedisplay driving mode at a touch sensing time when the panel 100 operatesin the display driving mode.

When the panel 100 operates in the touch driving mode, the sync signalgenerator 125 may output the first sync signal to the first and secondswitching parts 127 and 129. When the panel 100 operates in the displaydriving mode, the sync signal generator 125 may output the second syncsignal to the first and second switching parts 127 and 129.

Herein, the sync signal generator 125 may be a controller for thedisplay driver IC 120. The sync signal generator 125 may generate andoutput the sync signals according to the control by the controller forthe display driver IC 125.

Moreover, the sync signal generator 125 may transfer the sync signals tothe touch IC 130, thereby controlling the operation of the touch IC 130.

In another aspect, the first switching part 127 selectively connects thedriving pulse converter 123 or the common voltage generator 1211 to theplurality of driving electrodes 112 according to an output of the syncsignal generator 125. In another aspect, the second switching part 129selectively connects the touch IC 130 or the common voltage generator1211 to the plurality of sensing electrodes 114 according to the outputof the sync signal generator 125.

For example, when the first sync signal outputted from the sync signalgenerator 125 is inputted, the first switching part 127 may connect thedriving electrodes 112 to the driving pulse converter 123, and thesecond switching part 129 may connect the sensing electrodes 114 to thetouch IC 130.

In other words, when the panel 100 operates in the touch driving mode,in order for the driving electrodes 112 and sensing electrodes 114 toperform the function of the touch electrode, the second driving pulseoutputted from the driving pulse converter 123 may be applied to thedriving electrodes 112, and the touch IC 130 may receive the sensingsignals from the sensing electrodes 114.

When the second sync signal outputted from the sync signal generator 125is inputted, the first switching part 127 may connect the drivingelectrodes 112 to the common voltage generator 1211, and the secondswitching part 129 may also connect the sensing electrodes 114 to thecommon voltage generator 1211.

Specifically, when the panel 100 operates in the display driving mode,in order for the driving electrodes 112 and sensing electrodes 114 toperform the function of the common electrode, the common voltageoutputted from the common voltage generator 1211 may be applied to thedriving electrodes 112 and the sensing electrodes 114.

In another aspect, the first switching part 127 may include a pluralityof switches 1270 that are respectively connected to the drivingelectrodes 112, and the second switching part 129 may include aplurality of switches 1290 that are respectively connected to thesensing electrodes 114. The plurality of switches 1270 and 1290 may beconnected to the plurality of driving electrodes 112 and the pluralityof sensing electrodes 114, respectively.

The number of switches included in the first switching part 127 may beequal to the number of all driving electrodes 112 built in the panel100, and the number of switches included in the second switching part129 may be equal to the number of all sensing electrodes 114 built inthe panel 100.

Accordingly, in the display device with an integrated touch screenaccording to some embodiments of the present disclosure, the displaydriver IC may internally have a function of switching the commonvoltage. Here, by using the gate high voltage (which is generated in thedisplay driver IC) without adding a separate circuit block forhigh-voltage driving so as to enhance the intensity of the touch sensingsignal, the existing touch IC may be used without manufacturing aseparate touch IC, thus saving the manufacturing cost.

According to additional embodiments of the present disclosure, thedriving pulse converter 123 and the first switching part 127 have beendescribed above as being included in the display driver IC 120, but thepresent disclosure is not limited thereto. According to anotherembodiment of the present disclosure, the driving pulse converter 123and the first switching part 127 may be included in a gate driver havinga Gate In Panel (GIP) type.

Referring to FIGS. 1 and 2, the touch IC 130 may generate the firstdriving pulse to apply the first driving pulse to the display drive IC120 and may receive the sensing signals from the display driver IC 120to detect whether there is a touch.

In one aspect, a driver 132 of the touch IC 130 is connected to thedriving pulse converter 123 of the display driver IC 120, and a sensingpart 134 is connected to the second switching part 129 of the displaydriver IC 120.

The touch IC 130 may generate the first driving pulse and apply thefirst driving pulse to the display driver IC 120, according to the syncsignal generated by the sync signal generator 125.

In detail, the touch IC 130 may operate in synchronization with thedisplay driver IC 120. When the panel 100 operates in the touch drivingmode, in order for the driving electrodes 112 and sensing electrodes 114to perform the function of the touch electrode, the driver 132 of thetouch IC 130 may generate the first driving pulse to apply the firstdriving pulse to the driving pulse converter 123, and the sensing part134 may receive the sensing signals, generated by the respective sensingelectrodes 114, from the second switching part 129.

In another aspect, the touch IC 130 may be connected to the displaydriver IC 120 through a Flexible Printed Circuit Board (FPCB) 131. Inanother embodiment of the present disclosure, the touch IC 130 may beincluded in the display driver IC 120.

Hereinafter, a relationship between the first and second driving pulseswill be described in more detail with reference to FIG. 4.

FIG. 4 is a timing chart showing outputs of a touch IC and a displaydriver IC according to a driving mode of a panel, in a display devicewith an integrated touch screen according to some embodiments of thepresent disclosure.

In the display device with an integrated touch screen according to someembodiments of the present disclosure, the driving electrodes 112 andsensing electrodes 114 built in the panel 100 may perform the functionof the common electrode and the function of the touch electrodetogether, and thus, the display device may operate in a time-divisiondriving based on the display driving mode and touch driving mode.

Therefore, as shown in FIG. 4, one frame (1 frame) in the time-divisiondriving may be divided into (i) a display period where the panel 100operates in the display driving mode according to the sync signal and(ii) a touch period where the panel 100 operates in the touch drivingmode. A touch driving may be turned off for the display period, and adisplay driving may be turned off for the touch period, thus minimizingsignal interference between the touch driving and the display driving.

-   -   In the touch period, the touch IC 130 may output the first        driving pulse, and the display driver IC 120 may output the gate        high voltage Vgh to the driving electrodes 112 when the first        driving pulse has a high level or outputs the touch sensing        reference voltage Vref to the driving electrodes 112 when the        first driving pulse has a low level. As shown in FIG. 4, the        touch sensing reference voltage Vref may be different from the        common voltage Vcom.

In the display period, the display drive IC 120 may output the commonvoltage Vcom to the driving electrodes 112.

According to some embodiments of the present disclosure, the displaydriver IC may internally has the function of switching the commonvoltage, and by using the gate high voltage (which is generated in thedisplay driver IC) without adding a separate circuit block forhigh-voltage driving so as to enhance the intensity of the touch sensingsignal, the existing touch IC may be used without manufacturing aseparate touch IC, thus saving the manufacturing cost.

It will be apparent to those skilled in the art that variousmodifications and variations can be made in the present inventionwithout departing from the spirit or scope of the inventions. Thus, itis intended that the present disclosure covers the modifications andvariations of this invention provided they come within the scope of theappended claims and their equivalents.

What is claimed is:
 1. A display device, comprising: a touch screencomprising a plurality of driving electrodes and a plurality of sensingelectrodes in a panel; a touch integrated circuit (IC) configured to:generate a first driving pulse; and receive a plurality of sensingsignals to detect a touch on the touch screen; and a display driverintegrated circuit (IC) configured to receive the first driving pulsefrom the touch IC and to provide the sensing signals from the sensingelectrodes to the touch IC, the display driver IC comprising: a voltagegenerator comprising: a common voltage generator configured to generatea common voltage (Vcom); a gate high voltage generator configured togenerate a gate high voltage (Vgh); and a touch sensing referencevoltage generator configured to generate a touch sensing referencevoltage (Vref) different from the common voltage Vcom; a driving pulseconverter configured to convert the first driving pulse into a seconddriving pulse with the gate high voltage Vgh as a maximum value and thetouch sensing reference voltage Vref as a minimum value; a sync signalgenerator configured to generate a first sync signal indicating a touchdriving mode and a second sync signal indicating a display driving mode;a first switching circuit configured to selectively provide, to thedriving electrodes: the second driving pulse in response to the firstsync signal; and the common voltage Vcom in response to the second syncsignal; and a second switching circuit configured to selectively connectthe sensing electrodes: to the touch IC to provide the sensing signalsto the touch IC in response to the first sync signal; and to the commonvoltage generator to provide the common voltage Vcom to the sensingelectrodes in response to the second sync signal.
 2. The display deviceaccording to claim 1, wherein the display driver IC further comprises agate driver, a data driver, and a controller.
 3. The display deviceaccording to claim 1, wherein the first and second sync signals aretransferred to the touch IC.
 4. The display device according to claim 1,wherein: each of the driving electrodes comprises sub drivingelectrodes; and the sub driving electrodes and the sensing electrodesare formed as one common electrode for a plurality of unit pixel groups.5. The display device according to claim 1, wherein the touch ICcomprises a driver and a sensing part connected to the display driverIC.
 6. The display device according to claim 1, wherein the touch ICcomprises: a driver connected to the driving pulse converter of thedisplay driver IC; and a sensing part connected to the second switchingpart of the display driver IC.
 7. The display device according to claim1, wherein the touch IC is connected to the display driver IC through aFlexible Printed Circuit Board (FPCB).
 8. A method of internallyswitching a common voltage in the display device of claim 1, comprising:applying the touch sensing reference voltage Vref to the sensingelectrodes during the touch driving mode; and sensing a change amount ofa mutual capacitance between the driving electrodes and the sensingelectrodes by the touch IC with the touch sensing reference voltage Vrefapplied to the sensing electrodes.
 9. The method of internally switchinga common voltage according to claim 8, further comprising: generatingand outputting by the sync signal generator: a first sync signalindicating the touch driving mode to the first and second switchingparts when the panel operates in the touch driving mode; and a secondsync signal indicating the display driving mode to the first and secondswitching parts when the panel operates in the display driving mode. 10.The display device of claim 1, wherein the display driver IC is furtherconfigured to provide the touch sensing reference voltage Vref to thesensing electrodes during the touch driving mode.
 11. The display deviceof claim 10, wherein the touch sensing reference voltage Vref providedto the touch sensing electrodes during the touch driving mode is aconstant direct current (DC) voltage different from the common voltageVcom.
 12. The display device of claim 10, wherein the touch IC isfurther configured to sense an amount of change in a mutual capacitancebetween the driving electrodes and the sensing electrodes with the touchsensing reference voltage Vref applied to the sensing electrodes duringthe touch driving mode.
 13. The display device of claim 1, wherein thefirst switching circuit includes a plurality of first switches, each ofthe plurality of first switches being connected to a corresponding oneof the driving electrodes and configured to selectively connect thecorresponding one of the driving electrodes to the driving pulseconverter in the touch driving mode or to the common voltage generatorin the display driving mode.
 14. The display device of claim 10, whereinthe second switching circuit includes a plurality of second switches,each of the plurality of second switches being connected to acorresponding one of the sensing electrodes and configured toselectively connect the corresponding one of the sensing electrodes tothe touch IC in the touch driving mode or to the common voltagegenerator in the display driving mode.
 15. The display device of claim1, wherein the driving pulse converter is further configured to: outputthe gate high voltage Vgh to the driving electrodes based on the firstdriving pulse having a high level; and output the touch sensingreference voltage Vref to the driving electrodes based on the firstdriving pulse having a low level.
 16. The display device of claim 1,wherein the display driver integrated circuit (IC) further comprises: agate driver to apply a scan pulse sequentially to a plurality of gatelines of the display device; and a data driver to apply a plurality ofimage data signals respectively to a plurality of data lines of thedisplay device.
 17. A display device, comprising: a touch screencomprising a plurality of driving electrodes and a plurality of sensingelectrodes in a panel; a touch integrated circuit (IC) configured to:generate a first driving pulse; and receive a plurality of sensingsignals to detect a touch on the touch screen; and a voltage generatorcomprising: a common voltage generator configured to generate a commonvoltage (Vcom); a gate high voltage generator configured to generate agate high voltage (Vgh); and a touch sensing reference voltage generatorconfigured to generate a touch sensing reference voltage (Vref)different from the common voltage Vcom; a driving pulse converterconfigured to convert the first driving pulse into a second drivingpulse with the gate high voltage Vgh as a maximum value and the touchsensing reference voltage Vref as a minimum value; a sync signalgenerator configured to generate a first sync signal indicating a touchdriving mode and a second sync signal indicating a display driving mode;a first switching circuit configured to selectively provide, to thedriving electrodes: the second driving pulse in response to the firstsync signal; and the common voltage Vcom in response to the second syncsignal; and a second switching circuit configured to selectively connectthe sensing electrodes: to the touch IC to provide the sensing signalsto the touch IC in response to the first sync signal; and to the commonvoltage generator to provide the common voltage Vcom to the sensingelectrodes in response to the second sync signal.
 18. The display deviceof claim 17, wherein the driving pulse converter and the first switchingcircuit are included in a gate-in-panel (GIP) type gate driver.
 19. Thedisplay device of claim 17, wherein the driving pulse converter isfurther configured to: output the gate high voltage Vgh to the drivingelectrodes based on the first driving pulse having a high level; andoutput the touch sensing reference voltage Vref to the drivingelectrodes based on the first driving pulse having a low level.
 20. Thedisplay device of claim 17, wherein the touch sensing reference voltageVref is configured to be provided to the sensing electrodes during thetouch driving mode.
 21. The display device of claim 20, wherein thetouch sensing reference voltage Vref provided to the touch sensingelectrodes during the touch driving mode is a constant direct current(DC) voltage different from the common voltage Vcom.